For example, as described in the Patent Publication 1, it is known that an anchor bolt is inserted into an attachment bore which is bored in a rock wall with a drill and fixed in the attachment bore.
Specifically the anchor bolt described in the Patent Publication 1 has a taper member (expansion nut) with six inclined surfaces, six abutment parts (leaves) which abut, the respective inclined surfaces of the taper member, and a rod (bolt) which is threadably engaged with an internal thread of the taper member.
After the anchor bolt is inserted into the attachment bore, the rod is turned to apply a pulling force to the taper member in a direction of removing the taper member from the attachment bore. Then, the taper member is moved toward an opening of the attachment bore (downward in FIG. 4 in the Patent Publication 1) to allow the inclined surfaces of the taper member to abut inner surfaces of the respective abutment parts and to push the abutment parts toward an inner peripheral surface of the attachment bore. Thus, outer peripheral surfaces of the abutment parts are pressed against the inner peripheral surface of the attachment bore so that the anchor bolt is fixed (secured) in the attachment bore.